1. Field of the Invention
The present invention relates to a substrate member and a method of manufacturing a chip.
2. Description of the Related Art
A substrate member, in which a plurality of chip regions having circuit patterns are formed on a silicon wafer (substrate) by repeating process of photoresist coating, exposure, development, etching, and so on, is manufactured as a pre-process in semiconductor manufacturing. The substrate member manufactured in pre-process is divided (diced) into individual chips, assembled, and mounted in a post-process to manufacture semiconductors. Chip arrangements for forming the greatest number of rectangular chips possible on a circular substrate, dicing techniques for reducing the width of dicing streets (scribe lines), and so on are being considered as ways to increase a number of chips obtained from a substrate member. Japanese Patent Laid-Open No. 2012-89730 discloses a dicing technique that irradiates a substrate with a laser so that light is condensed on the interior of the substrate in order to reduce the width of dicing streets.
However, when the dicing technique disclosed in Japanese Patent Laid-Open No. 2012-89730 was employed, there was a possibility of melting, whiskers, crystal defects and so on possibly occurring due to heat produced by the laser irradiation in the vicinity of cutting lines in the substrate member. For this reason, short circuit, disconnection, a change in resistance and so on were generated, and thereby areas in the vicinity of cutting lines could be susceptible to breakdowns in the circuit patterns and so on. Thus, there was a problem of not significantly reducing the width of the scribe lines. Further, when dicing using a blade, it was necessary to maintain a width of the blade in the range from 20 to 35 μm. In addition, there was a possibility that damage could be caused by coolant for cooling the blade or by cleaning fluid used to remove shavings. Therefore, there was a problem of not being able to reduce the width of the scribe lines beyond the reduction achieved by laser dicing.